Organolanthanoids. III. Preparations and properties of some Di(alkynyl)lanthanoids

Abstract

From reactions between di(alkynyl)mercurials and lanthanoid elements in tetrahydrofuran or 1,2-dimethoxyethane, the organolanthanoids (PhCC)₂Yb and (PhCC)₂Eu(thf)_0.25 (thf = tetrahydrofuran) have been isolated, and (RCC)₂M (R = Ph or Bu^t, M = Yb; R = Ph, M = Eu) characterized in solution. Bis(phenylethynyl)ytterbium has also been obtained by ligand exchange between (C₆F₅)₂Yb or (Bu^tCC)₂Y and phenylacetylene. The di(alkynyl)lanthanoids are considered to have associated structures with bridging alkynyl groups. Hydrolysis of (RCC)₂M derivatives yields acetylenes RCCH, together with alkenes RCHCH₂ (greater for M = Yb than M = Eu), and, when M = Yb, R = Ph, a little ethylbenzene.